1. Field of the Invention
This invention relates to a process for preparing a polyvinylpyrrolidone-iodine complex, generally called PVP-iodine, and, more particularly, it is concerned with an improved process which provides a stable complex for use as a germicidal and bactericidal composition.
2. Description of the Prior Art
PVP-iodine has been used extensively in hospitals and elsewhere for some time because of its germicidal, bactericidal, fungicidal and generally disinfecting properties. Usually it is sold as a brown powder, which contains about 10% available, or active iodine, and about 5% inactive iodine, in the form of the iodide ion.
The known processes for making commercial PVP-iodine are represented by such patents as U.S. Pat. Nos. 2,706,701, 2,739,922, 2,826,532, 2,900,305, 3,028,300, German Pat. No. 1,037,075 and German OL No. 2,439,197. These prior art processes are characterized by being deficient in one or more respects, particularly in that they are time-consuming and expensive, or require a large amount of iodine to produce a stable complex having an acceptable available iodine level.
Accordingly, it is an object of the present invention to provide an improved commercial process for making PVP-iodine by an economical method, which provides a high level of active iodine in the complex without requiring an excessive amount of iodine reactant, and which produces a stable composition of light coloration.
These and other objects and features of the invention will become apparent from the following more particular description of the invention.